Perforated sheet



1,540,325 I J. M. FULLER PERFORAT-ED S HEET Juhe Z, 1925.

Filed' May 5, 1919 Patented June 2, 1925.

UNITED STATES 1,540,325 PATENT OFFICE.

J'UDSON M. FULLER, or OAK PARK. ILLINOIS, ASSIGNORY TO THE HARRINGTON AND KING PERFORATING 00., or CHICAGO. ILLINOIS, A CORPORATION or ILLINOIS.

rnnroaA'rEn SHEET.

Application filed May 5, 1919.

To all whom it may concemr.

Be it known that I, J UDSON M. .FFILLER, a citizen of the United States, residing at Oak Park, in the county of Cook and the State of Illinois, have invented certain new and useful Improvements in Ierforated Sheets, of which the following 18 a specification, reference being had to the accompanying drawings, forming a partthereof.

This invention relates to a supporting sheet adapted for various purposes and'especially for insertion between a filter cloth, a fine mesh metal screen or similar flexible and pervious element, and a rigid frame or backing wall, for the purpose of spacing the filter sheet or screen from such back1ng,- the supporting sheet being designed to present the minimum of obstruction to the flow of the filtrate or liquor, both through the screen and in the space formed between such screen and the rigid backing. It consists of the features of construction hereinafter described and shown in the drawings as 111- dicated by the claims.

In the drawings: 0

Figure' 1 is a bottom plan view of a fragment of a sheet of perforated material embodying this invention.

Figure 2 is a sectional view of the sheet shown in Figure 1, drawn to a slightly larger scale and taken as indicated at line 22 on Figure 1.

Figure 3 is a bottom plan view of a perforated sheet of slightly different form but also embodying the invention.

Figure 4 is a section taken as indicated at line 4- l on Figure 3. p 7

Figures 5 to 14 inclusive show various modified arrangements of rectangular perforations with rectangular lugs extend ng from one or more edges thereof, but all 1neluded within the scope of this invention In each case the view is a bottom plan of a fragment of a sheet.

Figures 15 to 18 inclusive are bottom plan views of further modifications in which the polygonal perforations are shown as triangular with supportmg lugs extending from either one or two sides or edges of each aperture.

Figure 19 is a bottom plan view of a fragment of a sheet illustrating one more mod1- fication in which the apertures are hexagonal with supporting lugs extending from several edges of each.

pressure such that if a filtering Serial No. 294,842.

There are many situations in manufacturing apparatus and processes, particularly those involving the operations of straining,

filtering or screening, in which it is desir-.

able to support a screen or filter cloth of relatively fine mesh against the fairly heavy pressure involved in the operation. Usually a screen or cloth, whether of perforated metal, woven wire, or vegetable fabric, if it is of sufficiently fine mesh to perform the work required, it is necessarily rather thin and quite flexible, but not particularly strong. The operations in which such pervious or perforate sheets are employed, how ever, frequently involve the use of heavy membrane were merely stretched over a marginal sup porting frame, it would be Wholly inadequate to withstand such pressure and would be promptly ruptured. Under such circumstances the filter sheet or screen is therefore usually supported by a fairly rigid backing wall extending over the entire exposed area of the pervious sheet but spacedfrom it in a substantially parallel plane to permit of drainage of the filtrate or liquor passing through the sheet under the pressure applied, and this spaced relation is maintained by either providing the backing wall with a corrugated surface coming in contact with the pervious sheet only at certain lines or points in its area, or providing a member formed to serve in the same way as a spacing element supported on the rigid wall and contacting with the pervious sheetat regularly spaced points, leaving relatively small, though many, unsupported areas which are unobstructed for the passage of the filtrate through them. It is the purpose of the present invention to provide such a supporting element to be interposed in apparatus presenting the above-indicated requirements.

The specimen fragn'ient of a perforated sheet as shown in Figure 1 may be understood as of sheet metal of a moderate gauge or thickness having two series of apertures, 1, and 2, arranged in alternating rows,the apertures, 2, being punched cleanly through by complete removal of the material representing their respective areas, while the apertures, 1, are formed by cutting this material free from the remainder of the sheet at two opposite and parallel edges, and bending it to extend as a pair of transverse lugs or feet, 3, from the other pair of opposite and parallel edges which complete the outline of each aperture, 1, as

shown. If the lugs thus formed would be longer than desired, the first o ration in forming the apertures, 1, would e to punch out a middle section of the area, thus, in effect, cutting-off the extreme end portion of each lug, 3, before bending out the latter.

In this view, the a ertures, 2, are shown arranged in staggere relation to the apertures, 1, of the alternate rows, and the result is indicated in section in Figure 2, which shows how the bending of the lugs, 3, tends toarch up the material at 4, between the adjacent-apertures, 2, and between the lugs of adjacent rows of the type of apertures, -1. This makes a corlugated surface at the side of the sheet A, opposite that from which the In 's, 3, extend, so that, if, as indicated in. igure 2, this sheet, A, is inter osed between a rigid backingwall, X, an a finely perforated, thin screen, Y, or other pervious sheet, said sheet, A, will stand in actual contact with the sheet, Y, at the minimum area, because of the arched formation of the parts, 4, which thus stand above the remainder of the uncut area of sheet, A, and tend to support the membrane or sheet, Y, slightly spaced away even from this remaining area of the interposedelement, A. Thus a large percentage of the total area of the pervious member, Y, is left quite unobstructed for the passage of the filtrate through its perforations or meshes. The drawing is not intended to indicate any particular direction of flow for the filtrate over the surface of the backing wall, X, but if this part stands vertical or inclined it will be evident that such flow will be least obstructed if the sheet, A, is arranged with its feet or lugs, 3, standing edge-wise in the current of the fiow,-that is, so that Figure 2 wouldpro'perly represent a section taken looking in the direction of such flow or movement.

A modified design of sheet is shown at B, in Figures 3 and 4, in which an aperture is indicated at 1, and is of the t pe formed by bending out at one of its e ges, a lug, 3, for contact with the supporting surface of wall X, but for the better distribution of these supporting lugs over the under surface of the pervious sheet, shown in Figure 4 as a woven wire screen, Z, these lugs, 3, are .bent alternately from the opposite sides of adjacent apertures, 1, of each row.

Figure 5 shows a fragment, C, in which the lugs, 3, are all arranged at the same, or'corresponding edges of their respective apertures, 1. In Figure 6, the fragment, D, presents a similar arrangement, except that the apertures, 1, themselves are placed in staggered relation. In Figure 7, the fragment, E, has staggered apertures, 1, in which the lugs, 3, extend all from the same or corresponding sides of the openings, as distinguished from the top or bottom, so that the bent lugs, 3, are themselves in staggered rows if considered in their relation edge-wise to each other.

The openings shown in the first seven figures of the .drawing are a proximate y square, but to indicate that t is is not an essential feature, the specimens, F, G, H, I, J, K and L, shown in Figures 8 to 14, inclusive, are made with oblong apertures, all designated by the character, 1, and each opening formed with one or more lugs, 3, extending from an edge or certain edges, for sup orting the screen or filter cloth, as 9.1- rea g described. The specimens, M, N, O, and shown in Figures 15 to 18, inclusive, present triangular apertures variously arranged in respect to each other, and some with one and others with two lugs, 3, bent out from their edges. Specimen, Q, of

Figure 19, shows an even more elaborate design comprising polygonal apertures of hexagonal form, each having In S, 3, bent out from several of its edges. is multiplication of examples is merely to em hasize the fact that polygonal apertures 0 three, four, six, or any other number of sides may be emplo ed without departure from the spirit an scope-of this invention, and that it'is not of particular importance whether each of such apertures is made with only a single lug or oot, 3, or with several such supporting members, bent off from its edges; nor is it important that every one of the openings in the interposed sheet be formed with such lugs; and many additional modifications of structure and arrangement may still be made within the spirit of the invention and of the appended claims defining the same.

i I claim:

' 1. A support for a filter screen or the like comprising a reticulated sheet having polygonal apertures with the material cut from said apertures bent to extend perpendicularly from the plane of the sheet at the side opposite its screen supporting surface and from one or more edges of said apertures, but not from all edges of any, thus forming lugs for spacing the sheet from a supporting surface; the outer ends of such lugs being cut on straight lines lying in a common plane parallel to that of the sheet.

2. A sheet, having polygonal apertures arranged in staggered rows with the ma terial cut from said apertures bent to extend from each of two opposite sides of the apertures of each alternate row whereby the material between the a ertures of intervening rows is arched up etween adjacent of the sheet is corrugated.

3.'In a sheet as defined in claim 1, the

' said apertures being rectangular, and the lugs extending therefrom being also rectangular. r

4. A sheet having rectangular apertures arranged in staggered rows with rectangular lugs bent to extend from each of two opposite sides ofeach aperture of each alternate row, whereby the material between the apertures of intervening rows is arched up 10 between adjacent lugs of the rows adjacent, and thus the surface of the sheet is corrugated.

In testimon whereof, I have hereunto set my hand at hicago, Illinois, this 2nd day 15 of May, 1919.

JUDSON M. FULLER. 

